package lab02.test28;

import java.util.InputMismatchException;
import java.util.Scanner;

public class Test28 {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);

        try {
            System.out.println("输入圆的半径：");
            double a = sc.nextDouble();
            double s = 3.14 * a * a;
            System.out.println("面积：" + s);

        } catch (InputMismatchException e) {
            System.out.println("你输入的数据错误！");

        }

    }
}


